If you are working with a GUI script within PowerShell Studio and find that you need to edit the exported script to modify the control\u2019s initialization, then you are doing something wrong.<\/p>\n
Don\u2019t get me wrong, modifying and initialization of control properties is not the issue; in fact that it part of writing a GUI. What I\u2019m referring to is the part where you are editing the exported scripts.<\/p>\n
If you are editing the exported script:<\/p>\n
1. You are creating an extra step which means you need to export and modify the script anytime<\/span> you make a change to the original file.<\/p>\n 2. It is time consuming and unproductive.<\/p>\n 3. If you are working with Source Control or within a team environment, chances are the change will be missed or forgotten by somebody.<\/p>\n <\/p>\n So if I\u2019m not supposed to edit the exported script, then how do I initialize my controls?<\/strong><\/p>\n Thankfully WinForms provides a convenient place to initialize your GUI controls, the Form control\u2019s Load<\/em> event.<\/p>\n The Form control\u2019s Load<\/em> event is called right before the form is displayed, which makes it a perfect place to initialize your controls.<\/p>\n <\/p>\n Warning: Do not try to initialize a control outside an event block within the script.<\/span><\/p>\n 1. The control might not exist when this line is executed by PowerShell.<\/p>\n 2. If the control does exist, your changes will most likely get overwritten by the designer generated script.<\/p>\n Alternatives to the Load event:<\/strong><\/p>\n It is possible to use other events to trigger initialization. For example, some control sets such as the Chart \u2013 Disk Space<\/em> use the VisibleChanged<\/em> event to trigger initialization. This event is triggered when the control is displayed (such as when the form is loaded) or hidden using the Visible<\/em> property.<\/p>\n In the sample above, the control set initializes when the control becomes visible by checking its Visible<\/em> property.<\/p>\n <\/p>\n If your initialization script is running slow it can prevent the GUI from displaying in a timely manner or cause it to hang. In instances such as this, you might want to delay your initialization or simply run the query in a separate job then initialize and enable the controls after the job has completed the query.<\/p>\n Warning: You cannot access GUI controls directly from a Job. You must return the results first and then initialize the controls on the main thread \/ script.<\/span><\/p>\n For more details on how to use Jobs within a GUI script, please refer to the Creating Responsive Forms<\/a> article.<\/p>\n$formServices_Load<\/span>=<\/span>{\n <\/span>#TODO: Initialize Form Controls here\n<\/span> <\/span>#Load the services into the the combobox
<\/span>Load-ComboBox <\/span>-ComboBox <\/span>$comboboxServices <\/span>-Items<\/span> (<\/span>Get-Service<\/span>) <\/span>-DisplayMember<\/span> Name\n\n <\/span>#Display the computer name in the form's title
<\/span>$formServices<\/span>.Text <\/span>=<\/span>\"Services on $env:ComputerName\"<\/span>\n}<\/span><\/pre>\n$chartDiskSpace_VisibleChanged<\/span>=<\/span>{\n <\/span>if<\/span>(<\/span>$this<\/span>.Visible)\n {\n <\/span>Load-DiskChart<\/span>$this<\/span>\n }\n}<\/span><\/pre>\n